Vision is fundamental to the everyday behavior of most animals, including mammals, birds and insects. Most animals use vision to facilitate their social interactions, orientation and foraging behavior. The visual system of humans has been characterized as trichromatic; human visual pigments are maximally sensitive to wavelengths in three regions reds, greens and blues). Most birds are tetrachromatic; bird visual pigments and oil droplets are ultraviolet- or violet-sensitive (UVS, VS), as well as the short-, medium- and long-wavelength sensitive cones also found in humans (SWS, MSW, LWS). In contrast, most all other animals are sensitive to only two wavelength regions and as such are categorized as dichromatic.
Vertebrates generally have a single rod photopigment and up to four classes of cone photopigment (i.e. long-, middle-, and two short-wave sensitive visual pigments; Cowan et al. 2002). Most mammals are dichromatic, having two classes of cone photopigment (i.e. long- and short-wave sensitive visual pigments; David-Gray et al. 2002). The short-wave sensitive (SWS) visual pigments of vertebrate cone photoreceptors are divided into two molecular classes, SWS1 and SWS2. Only the SWS1 class is present in mammals. The SWS1 class has been subdivided into violet-sensitive (VS; peak maximum absorbance, or λmax=400-430 nm) and ultraviolet-sensitive visual pigments (UVS, λmax<380 nm; Cowing et al. 2002). Although ultraviolet (UV) sensitivity is widespread among animals it is considered rare in mammals, being restricted to the few species that have λmax<400 nm (Douglas and Jeffery 2014). Animals without UVS visual pigments, however, will be sensitive to UV wavelengths if they have ocular media that transmit UV wavelengths, as all visual pigments absorb significant amounts of UV if the energy level is sufficient (Douglas and Jeffery 2014).”
Although most animals are not maximally sensitive to full spectrum wavelengths (e.g. 300-1,400 nm), implications of this technology include behavioral responsiveness (e.g. 5% repellency or attraction) among dichromatic animals to wavelengths for which they are not maximally sensitive. This invention exploits the novel and non-obvious observation of behavioral responsiveness among dichromatic animals to wavelengths for which they are not maximally sensitive (e.g., <400 nm, >700 nm). This use of wavelengths independent of those that characterize dichromatic vision has implications for a myriad of applications for repellents and attractants of dichromatic animals.